Organosilicon compounds containing covalently bonded fluorescent groups are widely known in the literature.
Curable organopolysiloxanes containing chromophoric groups, which may also have fluorescent properties, are described in U.S. Pat. No. 3,741,932 (Minnesota Mining and Manufacturing Company, published on Jun. 26, 1973). The synthesis takes place by the ring-opening reaction of epoxy functions with sulfonamide-functional chromophores.
Fluorescent organopolysiloxanes for the treatment of hair are disclosed in U.S. Pat. No. 5,176,906 (Dow Corning Corporation, Jan. 5, 1993). Here, the claimed compounds are prepared via a nucleophilic substitution reaction of amine-functional polysiloxanes with fluorescent compounds having sulfonyl chloride groups.
Radiation-curing epoxy silicone-polyether block copolymers are described in U.S. Pat. No. 5,227,410 (General Electric Company, Jul. 13, 1993). By virtue of the polar structure of the block copolymers, sensitizers in the 200 ppm range can be clearly incorporated.
Organopolysiloxanes containing dansyl groups and curable thermally via a hydrosilylation reaction are described in EP-A 455 384 (Dow Corning Corporation, laid open on Nov. 6, 1991). The organopolysiloxanes containing vinyl and amine functions are modified, for example, using dansyl chloride and can then be cured fully using H-crosslinkers.
Fluorene-group-containing organopolysiloxanes for coatings are disclosed in U.S. Pat. No. 4,978,731 (Minnesota Mining and Manufacturing Company, published on Dec. 18, 1990). The preparation takes place via a hydrosilylation reaction of alkylfluorene with hydrogen-containing organopolysiloxanes. The labeled polysiloxanes serve to determine coating weight and coating defects.
One method of testing the curing performance of the silicones is described in EP-A 720 015 (Avery Dennison Corporation, laid open on Jul. 3, 1996), where polysiloxanes functionalized with pyrene groups enable on-line monitoring of curing.
Silanes containing fluorescent groups and secondary reactions with polyorganosiloxanes as chemical indicators in biological sensors are disclosed in U.S. Pat. No. 4,746,751 (Baxter Travenol Laboratories, published on May 24, 1988). The synthesis is based on a reaction of Grignard compounds with chlorosilanes.
Other organosilicon compounds containing fluorescent groups, especially compounds containing pyrene compounds, are disclosed in U.S. Pat. No. 4,866,152 (Dow Corning Corporation, published on Sep. 12, 1989). By eliminating water from pyrenealdehyde and amino-functional polysiloxanes, it is possible to achieve a covalent bond between the fluorescent agent and the polysiloxane.
Silicone resins having fluorescent properties are described in U.S. Pat. No. 3,427,273 (Owens-Illinois Glass Company, published on Feb. 11, 1969). The preparation involves reaction of bromonaphthalene with a lithium compound and further reaction with alkoxysilanes.